DNA-Based Enzyme Reactors and Systems

Peer reviewe

Self-Assembly of Amphiphilic Janus Dendrimers into Mechanically Robust Supramolecular Hydrogels for Sustained Drug Release

Peer reviewe

High-Generation Amphiphilic Janus-Dendrimers as Stabilizing Agents for Drug Suspensions

Pharmaceutical nanosuspensions are formed when drug crystals are suspended in aqueous media in the presence of stabilizers. This technology offers a convenient way to enhance the dissolution of poorly water-soluble drug compounds. The stabilizers exert their action through electrostatic or steric interactions, however, the molecular requirements of stabilizing agents have not been studied extensively. Here, four structurally related amphiphilic Janus-dendrimers were synthesized and screened to determine the roles of different macromolecular domains on the stabilization of drug crystals. Physical interaction and nanomilling experiments have substantiated that Janus-dendrimers with fourth generation hydro- philic dendrons were superior to third generation analogues and Poloxamer 188 in stabilizing indomethacin suspensions. Contact angle and surface plasmon resonance measurements support the hypothesis that Janus-dendrimers bind to indomethacin surfaces via hydrophobic interactions and that the number of hydrophobic alkyl tails determines the adsorption kinetics of the Janus-dendrimers. The results showed that amphiphilic Janus-dendrimers adsorb onto drug particles and thus can be used to provide steric stabilization against aggregation and recrystallization. The modular synthetic route for new amphiphilic Janus-dendrimers offers, thus, for the first time a versatile platform for stable general-use stabilizing agents of drug suspensions.Peer reviewe

Modular synthesis of self-assembling Janus-dendrimers and facile preparation of drug-loaded dendrimersomes

Materials and methods aimed at the next generation of nanoscale carriers for drugs and other therapeutics are currently in great demand. Yet, creating these precise molecular arrangements in a feasible and straightforward manner represents a remarkable challenge. Herein we report a modular synthetic route for amphiphilic Janus-dendrimers via a copper-catalyzed click reaction (CuAAC) and a facile procedure, using simple injection, to obtain highly uniform dendrimersomes with efficient loading of the model drug compound propranolol. The resulting assemblies were analyzed by dynamic light scattering and cryogenic transmission electronic microscopy revealing the formation of unilamellar and multilamellar dendrimersomes. The formation of a bilayer structure was confirmed using cryo-TEM and confocal microscopy visualization of an encapsulated solvatochromic dye (Nile red). The dendrimersomes reported here are tunable in size, stable over time and display robust thermal stability in aqueous media. Our results expand the scope of dendrimer-based supramolecular colloidal systems and offer the means for one-step fabrication of drug-loaded dendrimersomes in the size range of 90–200 nm, ideal for biomedical applications

Janus-dendrimer supramolecular structures as delivery agents for small molecules, peptides and proteins

Janus-dendrimers are synthetic amphiphiles formed by linking two chemically distinct hydrophilic and hydrophobic dendrons by their core, which can self-assemble as vesicles (dendrimersomes) or fibres in aqueous solutions, as well as in biological media. This research shows that the dendrimersome scan differentially encapsulate drug compounds, are stable for long periods of time, and can be annealed from 22 °C to 70 °C with minimal change (2-5 nm)in their hydrodynamic radius [1].Also, by modulating the hydrophilic branch generation we found that Janus-dendrimers were also able to self-assemble into a variety of other architectures such as fibres, giving rise to supramolecular hydrogels capable of encapsulating and releasing small molecules, peptides, and proteins[2],or even function as colloidal suspensions’ stabilizers [3].Thus, the small library of Janus-dendrimers reported herein expand the scope of dendrimer-based supramolecular drug delivery systems and suggest that these materials can be further used in biomedical sol–gel applications

Dass, solkraft och hållbarhet

Dass, solkraft och hållbarhet – Mänskligheten är ingen ö av Pia Prost – Ålands resa mot hållbarhet – mål för en bärkraftig skärgård av Lotta Nummelin – Kan man reparera havet? av Christoffer Boström – Att möta utmaningarna på Europas små öar av Camille Dressler – Om Simskäla, från olika håll av Christian Pleijel – Biogas som landsbygdens energikälla av Mats Nurmio – Med både traditioner och solenergi som barlast av Sami Uotinen – Snorgärsen tar plats av Harriet Strandvik – På naturens villkor av Pia Prost – Torrtoaletter i skärgården - en billig och bra lösning av Petri Huovila – Dasstömning – nästan som en dans på rosor av Nina Söderlund – Biosfärområden och FNs hållbarhetsmål av Katja Bonnevier och Pia Prost – Elektras första sommar av Pia Prost – Avhandlingar – HÒLA! Hasta La Vista av Aarón Blanco Tejedor Bokhörnan: – När Pommern lade ut på minuten av Thure Malmberg – Lyckad bokfest på Jurmo Patrik Bengtfolks – DefenceArch av Marcus Lepola – Skärinytt – Sista bilde

Risks and benefits of centralized and decentralized cryptocurrency exchanges and services

Opinnäytetyössä tarkastellaan hajautetun rahoituksen kehittyvää alaa ja pyritään auttamaan alasta kiinnostuneita valitsemaan oikea alusta jolla osallistua. Jotta valistuneen valinnan tekeminen asiassa olisi vielä helpompaa, esitellään uusia merkityksellisiä teknologioita, kuten kryptovaluutat sekä älykkäät sopimukset. Sekä keskitettyjen että hajautettujen pörssien ja palvelujen tarjoamien hyötyjen ja riskien määrittämiseksi kerättiin tietoja ryhmältä ihmisiä, jotka ovat käyttäneet molempia alustatyyppejä. Tiedot kerättiin käyttäjäkyselyllä kryptovaluuttaan liittyvässä keskusteluryhmässä ja haastattelemalla sekä keskitettyjen että hajautettujen alustojen edustajia. Johtopäätöksenä on, että keskitetyt pörssit ja palvelut ovat aloittelijalle ystävällisempiä ja turvallisempia kuin hajautetut pörssit ja palvelut. Jälkimmäiset tarjoavat kuitenkin paljon enemmän kaupankäyntimahdollisuuksia käyttäjille, joilla on tarvittava kokemus ja riskinottohalukkuus.The thesis takes a close look at the emerging industry of decentralized finance and aims to help those interested in the industry to choose the right platform to get started with. To further help with making an educated choice on the matter, new relevant technologies such as cryptocurrencies and smart contracts are introduced. To determine the benefits and risks presented by both centralized and decentralized exchanges and services, data was collected from a group of people who have used both types of platforms, and from two cryptocurrency exchange representatives. The data was collected with a user survey in a cryptocurrency-related chat group and by conducting interviews with representatives from both centralized and decentralized platforms. The conclusion is that centralized exchanges and services are more beginner friendly and secure than decentralized exchanges and services. The latter however provides much greater trading opportunities to users who have the necessary experience and risk appetite

3,4-Dimethoxy-4'-methylbiphenyl

In the title compound, C15H16O2, the dihedral angle between the planes of the aromatic rings is 30.5 (2). In the crystal, molecules are linked via C—HO hydrogen bonds and C— H interactions, forming a two-dimensional network lying parallel to (100).peerReviewe

Methyl 3',4',5'-trimethoxybiphenyl-4-carboxylate

In the title compound, C17H18O5, the dihedral angle between the benzene rings is 31.23 (16). In the crystal, the molecules are packed in an antiparallel fashion in layers along the a axis. In each layer, very weak C—HO hydrogen bonds occur between the methoxy and methyl ester groups. Weak C— H interactions between the 40 - and 50 -methoxy groups and neighbouring benzene rings [methoxy-C–ring centroid distances = 4.075 and 3.486 A˚ , respectively] connect the layers.peerReviewe